<!DOCTYPE html>
<script src="../include.js"></script>
<body>
    <iframe id="target" src="about:blank"></iframe>
    <script>
        asyncTest(done => {
            window.addEventListener("message", event => {
                println(event.data);
                done();
            });
            var script = target.contentDocument.createElement("script");
            script.innerHTML = `parent.postMessage("message from test iframe", "*");`;
            target.contentDocument.body.appendChild(script);
        });
    </script>
</body>
